1. Field
The following description relates to optical Ethernet transmission technology, and more particularly, to an equalization apparatus and method of compensating a distorted signal received through a serial data link.
2. Description of the Related Art
The growing demand for multimedia data communication is resulting in network equipment that can transmit data at several tens of gigabits per second (Gb/s). Data received by a multimedia data receiving apparatus contains various kinds of noise.
According to the Institute of Electrical and Electronic Engineers (IEEE) 802.3ba standard, ultra-high-speed data communication systems should transmit data using a multi-channel method. For example, 40 G of data should be transmitted using four 10 Gb/s lines (channels).
For high-speed multimedia data transmission, a cable-based high-speed serial transmission method is far more advantageous than a conventional bus-based parallel transmission method, in terms of system performance and cost.
Meanwhile, the increase in data transmission speed is creating problems such as signal loss and crosstalk (e.g., near-end crosstalk loss (NEXT) and far-end crosstalk loss (FEXT)) in a system backplane. To solve these problems, channel performance must be improved, which can be achieved by correcting the amplification of a signal or the modification of the signal, which occurs in the process of transmitting the signal, at the data transmitting or receiving end.
Specifically, inter-symbol interference (ISI) in a communication channel stems from channel impedance discontinuities, linear amplification, and phase distortion. Since ISI affects other adjacent channels, it must be minimized. To remove ISI, a maximum likelihood sequence detector (MSLD) or an equalizer is being used.